#pragma once

#include "IGUIElement.h"

namespace mycge
{
    namespace gui
    {
        //! An enum for the different types of GUI font.
        enum EGUI_FONT_TYPE
        {
            //! Bitmap fonts loaded from an XML file or a texture.
            EGFT_BITMAP = 0,

            //! Scalable vector fonts loaded from an XML file.
            /** These fonts reside in system memory and use no video memory
            until they are displayed. These are slower than bitmap fonts
            but can be easily scaled and rotated. */
            EGFT_VECTOR,

            //! A font which uses a the native API provided by the operating system.
            /** Currently not used. */
            EGFT_OS,

            //! An external font type provided by the user.
            EGFT_CUSTOM
        };

        //! Font interface.
        class IGUIFont
        {
        public:

            //! Draws some text and clips it to the specified rectangle if wanted.
            /** \param text: Text to draw
            \param position: Rectangle specifying position where to draw the text.
            \param color: Color of the text
            \param hcenter: Specifies if the text should be centered horizontally into the rectangle.
            \param vcenter: Specifies if the text should be centered vertically into the rectangle.
            \param clip: Optional pointer to a rectangle against which the text will be clipped.
            If the pointer is null, no clipping will be done. */
            virtual void Draw( const wstring& strText, const Rect<int>& rcPosition,
                D3DCOLOR color, bool bHcenter = false, bool bVcenter = false,
                const Rect<int>* rcClip = NULL ) = 0;

            //! Calculates the index of the character in the text which is on a specific position.
            /** \param text: Text string.
            \param pixel_x: X pixel position of which the index of the character will be returned.
            \return Returns zero based index of the character in the text, and -1 if no no character
            is on this position. (=the text is too short). */
            virtual int GetCharacterFromPos( const wchar_t* wcsText, int nPixel_x ) const = 0;

            //! Returns the type of this font
            virtual EGUI_FONT_TYPE GetType() const { return EGFT_CUSTOM; }

            //! Sets global kerning width for the font.
            virtual void SetKerningWidth ( int nKerning ) = 0;

            //! Sets global kerning height for the font.
            virtual void SetKerningHeight ( int nKerning ) = 0;

            //! Gets kerning values (distance between letters) for the font. If no parameters are provided,
            /** the global kerning distance is returned.
            \param thisLetter: If this parameter is provided, the left side kerning
            for this letter is added to the global kerning value. For example, a
            space might only be one pixel wide, but it may be displayed as several
            pixels.
            \param previousLetter: If provided, kerning is calculated for both
            letters and added to the global kerning value. For example, in a font
            which supports kerning pairs a string such as 'Wo' may have the 'o'
            tucked neatly under the 'W'.
            */
            virtual int GetKerningWidth( const wchar_t* wcsThisLetter=0, const wchar_t* wcsPreviousLetter = NULL ) const = 0;

            //! Returns the distance between letters
            virtual int GetKerningHeight() const = 0;

            //! Define which characters should not be drawn by the font.
            /** For example " " would not draw any space which is usually blank in
            most fonts.
            \param s String of symbols which are not send down to the videodriver
            */
            virtual void SetInvisibleCharacters( const wchar_t *str ) = 0;
        };
    }
}